https://starwars.fandom.com/wiki/Executioner_trooper

Executioner troopers, also known as First Order Judicial Stormtroopers or First Order stormtrooper executioners, were First Order stormtroopers randomly selected from existing ranks and assigned to dispense final justice on enemies and traitors of the First Order.

(I couldn't find a Minecraft version of the weapon so I had to use a real-life version and scale with it :/)